Figure 5From: Scoliosis corrective force estimation from the implanted rod deformation using 3D-FEM analysisRelationship between screw number and forces on screws. The pull out force exerted on the apical screw decreased in an exponential manner when screw number increased. Pull out force at the apical level on the concave side was 4.1 fold greater in the apex only model (screw number = 3) than all inserted model (screw number =10).Back to article page